A setting tool for use inside a well bore casing having an upper portion, a lower portion, and a wrap spring. The upper portion includes a mandrel coupled to a connecting line. The upper portion is configured to receive an input. The lower portion includes a first sleeve configured translate along an axis of the setting tool. The lower portion is selectively coupled to the upper portion. The wrap spring has a torsional preload and is coupled to the upper portion and the lower portion. The wrap spring is configured to selectively release the lower portion and upon reception of the input, such that the first sleeve is permitted to translate along the axis.
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14. A method of operating a setting tool, the method comprising:
securing a lower portion of the setting tool to an upper portion of the setting tool, the securing including threading a power sleeve onto a mandrel;
applying a torsional preload to a wrap spring that extends about the mandrel and into an aperture in the power sleeve, the wrap spring being configured to selectively retain the relative position of the upper portion to the lower portion by preventing the power sleeve from rotating relative to the mandrel;
attaching a connecting line to the upper portion;
lowering the setting tool within a casing sufficient to obtain a desired depth; and
applying an input through the connecting line to the setting tool, so as to activate the setting tool.
1. A setting tool for use in a well bore casing, comprising:
an upper portion having a mandrel and configured to receive an input, so as to induce relative motion of the mandrel within the casing;
a lower portion having a first sleeve configured to translate along an axis of the setting tool, the lower portion coupled to the upper portion;
a power sleeve extending into the upper and lower portions, the power sleeve being threadedly connected to the mandrel; and
a wrap spring extending about the mandrel and into an aperture in the power sleeve, the wrap spring being configured to accept a torsional preload to secure the first sleeve to the upper portion by preventing the power sleeve from rotating relative to the mandrel, the wrap spring being configured to selectively release the first sleeve from the upper portion upon reception of the input.
2. The setting tool of
3. The setting tool of
4. The setting tool of
an index sleeve surrounding the mandrel;
an index slot extending through the index sleeve; and
an index pin configured to translate within the index slot in response to the input;
wherein the index sleeve is configured to rotate around the mandrel as the index pin translates within the index slot.
5. The setting tool of
a swivel piece extending around a periphery of the mandrel and configured to rotate in relation to the mandrel; and
an L-slot pin coupled to the swivel piece and configured to rotate with the index sleeve within an L-slot, the L-slot pin configured to selectively restrict movement of the mandrel along the axis.
6. The setting tool of
a short sleeve extending around a periphery of the mandrel, the short sleeve configured to selectively secure the wrap spring, so as to maintain the torsional preload.
7. The setting tool of
8. The setting tool of
9. The setting tool of
10. The setting tool of
11. The setting tool of
a first fluid chamber in communication with the lower portion and configured selectively store an incompressible fluid; and
a metering port in fluid communication with first fluid chamber, the metering port being configured to regulate the flow of fluid from the first fluid chamber in response to the relative motion of the lower portion.
12. The setting tool of
a telescoping piston slidingly coupled to the lower portion, the telescoping piston being configured to translate along the axis in response to pressure from the incompressible fluid exiting through the metering port.
13. The setting tool of
a second fluid chamber in communication with the telescoping piston and being configured to retain a compressible fluid, the telescoping piston separating the compressible fluid from the incompressible fluid; and
wherein the second fluid chamber is configured to bias the telescoping piston against the incompressible fluid.
15. The method of
coupling a downhole completion tool to the lower portion.
16. The method of
17. The method of
18. The method of
selectively releasing the wrap spring from the upper portion;
wherein the lower portion translates in response to external forces.
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1. Field of the Invention
The present application relates to setting tools for use in well bores, as well as methods of using such setting tools. In particular, the present application relates to a hydrostatic setting tool.
2. Description of Related Art
Prior downhole tools are known, such as frac plugs and bridge plugs. Such downhole tools are commonly used for sealing a well bore. These types of downhole tools are usually coupled to a setting tool and typically can be lowered into a well bore in an unset position until the downhole tool reaches a desired setting depth. Upon reaching the desired setting depth, the downhole tool is set, or activated, by firing explosive charges or by transmitting electrical signals within the well bore.
Such methods are typically more complex and generally generate more risk. For example, there is a risk that the electrical setting signal could prematurely fire a perforating gun or short out. Additionally, the cost of using explosives can be expensive and hazardous. Likewise, the turn around time required to reset the setting tool for another use is typically lengthened due to the care and precautions dealing with explosives. A safer, more simplified, and cost effective method of setting downhole tools is needed.
Although the foregoing designs represent considerable advancements in the area of setting tools, many shortcomings remain.
The novel features believed characteristic of the invention are set forth in the appended claims. However, the invention itself, as well as a preferred mode of use, and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein:
While the downhole tool of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the process of the present application as defined by the appended claims.
Illustrative embodiments of the preferred embodiment are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
In the specification, reference may be made to the spatial relationships between various components and to the spatial orientation of various aspects of components as the devices are depicted in the attached drawings. However, as will be recognized by those skilled in the art after a complete reading of the present application, the devices, members, apparatuses, etc. described herein may be positioned in any desired orientation. Thus, the use of terms such as above, below, upper, and lower to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the device described herein may be oriented in any desired direction.
Referring now to
Setting tool 100 will be described herein as having an upper portion 91 and a lower portion 93. Due to the interactivity of the various elements of setting tool 100, a clear visual distinction between portions 91, 93 are difficult. However, portions 91, 93 are depicted in
Setting tool 100 is configured to set the downhole completion tool without the need of explosives or electrical influence within casing 99. As such, the preferred embodiment uses a mechanical input exerted upon mandrel 101 to position and activate setting tool 100.
Setting tool 100 is configured to translate within well bore casing 99. Setting tool 100 may be set at any desired depth within the casing 99. While lowering setting tool 100, fluid is permitted to pass between portions of setting tool 100 and casing 99. A description of the individual portions and parts of setting tool 100 will be described first in
Referring now also to
Setting tool 100 includes a mandrel 101 extending approximately half the length of setting tool 100. Mandrel 101 has upper threaded portion 97 configured to accept a variety of other tools or devices for operation within the casing 99 as described previously. A friction spring carrier 103 is disposed around the external surface of mandrel 101 and configured to permit relative motion between mandrel 101 and friction spring carrier 103. A friction spring carrier bolt 121 is threadedly coupled to mandrel 101. The head of friction spring carrier bolt extends within a slot 123 in friction spring carrier 103. The head permits the relative motion between friction spring carrier 103 and mandrel 101 in the axial direction. The head is also configured to prevent radial motion of friction spring carrier 103 around the periphery of mandrel 101.
A plurality of friction springs 105 are coupled to friction spring carrier 103. Friction springs 105 are resilient members that bow outwardly from the outer surface of friction spring carrier 103 and contact an inner surface of casing 99. Friction springs 105 are configured to act as leaf springs to assist in keeping setting tool 100 centered within casing 99. As such, an upper end of each friction spring extends into a respective spring slot 107, which allows room for friction spring 105 to extend and retract as needed. Spring slot 107 is formed by threadedly coupling a friction spring carrier cap 109 to an upper portion of friction spring carrier 103. A lower end of each friction spring 105 is attached to the friction spring carrier 103, for example using bolts or other such mounting hardware. Alternatively, the upper ends of the friction springs 105 can be fixed and the lower ends can be slidable. In the preferred embodiment, at least three friction springs 105 are used. However, it is understood that more or less may be used. Although it is not required, it is understood that the preferred embodiment will equally space friction springs 105 in relation to one another.
An index sleeve 111 is disposed around the external surface of a lower end of friction spring carrier 103. Index sleeve 111 has at least one index slot 113 that extends through the thickness of index sleeve 111.
Below friction spring carrier 103 and between index sleeve 111 and mandrel 101 is located a swivel piece 125. Swivel piece 125 is permitted to rotate freely around mandrel 101 as index sleeve 111 rotates. An L-slot pin 119 is threadedly coupled to swivel piece 125. The head of L-slot pin 119 extends externally, in relation to the threaded portion of pin 119, into an aperture within index sleeve 111. As index sleeve 111 rotates, L-slot pin 119 rotates in similar fashion. The lower end of L-slot pin 119 extends internally, in relation to the threaded portion of pin 119, into an L-slot 117 formed within the surface of mandrel 101. The lower end of L-slot pin 119 is not threaded. As index sleeve 111 and swivel piece 125 rotate radially around mandrel 101 the lower end of L-slot pin 119 translates within L-slot 117. At least one L-slot 117 is formed in the outside surface of the mandrel 101. In some embodiments, for example, identical L-slots 117 can be formed in opposing sides of the mandrel 101, thereby allowing for a plurality of L-slots 117 and corresponding L-slot pins 119 to be used.
A short sleeve 127 is located below index sleeve 111 around a periphery of mandrel 101 and swivel piece 125. Short sleeve 127 includes a retaining clip 129 extending radially around the inside surface of short sleeve 127. Retaining clip 129 is configured to contact a ledge 126 of swivel piece 125 so as to regulate relative motion between swivel piece 125 and short sleeve 127, such that short sleeve 127 remains adjacent index sleeve 111. Short sleeve 127 includes a sleeve bolt 130 threadedly coupled to mandrel 101. The head of sleeve bolt 130 extends externally within a vertical slot 131 located in short sleeve 127. Vertical slot 131 extends through the thickness of short sleeve 127. Vertical slot 131 is configured to permit sleeve bolt 130 and mandrel 101 to translate relative to short sleeve 127 and to restrict radial rotation of short sleeve 127 in relation to mandrel 101. In the preferred embodiment a plurality of sleeve bolts 130 and corresponding vertical slots 131 are used. Two are illustrated in
Mandrel 101 is threadedly coupled to a power sleeve 137. Power threads 141 define the type of threads used to couple mandrel 101 and power sleeve 137 together. Power threads 141 are configured to allow power sleeve 137 to rotate in relation to mandrel 101. Power threads are further configured to allow for a reduction in the force required to rotate sleeve 137 in relation to mandrel 101. For example, power threads can generate a 10 to 1 reduction in force. Although power threads 141 are used, it is understood that other types of threaded relationships may also be used. Furthermore, other methods of coupling mandrel 101 and power sleeve 137 are understood to be possible and permit relative rotation with respect to one another.
A wrap spring 135, under a torsional preload, is wound around mandrel 101 and power sleeve 137. An upper portion of wrap spring 135 is located beneath short sleeve 127. The upper portion of wrap spring 135 is releasably secured to short sleeve 127. As illustrated, a spring slot 133 is formed within short sleeve 127 to retain the upper portion of wrap spring 135. Spring slot 133 is defined by three sides, being open along a lower edge 128 of short sleeve 127. A lower portion of wrap spring 135 is secured within an aperture 139 located in power sleeve 137. In the preferred embodiment, mandrel 101 is configured to selectively release the upper portion of wrap spring 135 from short sleeve 127. In the preferred embodiment, the release of wrap spring 135 occurs as mandrel 101 translates with respect to short sleeve 127. Spring slot 133 is configured to permit wrap spring 135 to slide beyond edge 128. Although spring slot 133 has been illustrated as securing wrap spring 135, it is understood that other embodiments may be used to release wrap spring 135 as mandrel 101 translates along the axis of setting tool 100.
Wrap spring 135 operably couples upper portion 91 with lower portion 93 of setting tool 100. Upper portion 91 consists of those elements introduced above. For example, mandrel 101, short sleeve 127, index sleeve 111, friction spring carrier 103, and each of their associated parts are considered within upper portion 91. Upper portion 91 receives inputs and is configured to selectively release the torsional preload in wrap spring 135, thereby permitting power sleeve 137 to rotate. Lower portion 93 includes a connector sleeve 151, a locking pin 147, power sleeve 137, and pistons 161, 179. Lower portion 93 is configured to be selectively released from power sleeve 137 upon the unwinding of wrap spring 135.
Connector sleeve 151 extends around a periphery of power sleeve 137 and mandrel 101. Connector sleeve 151 is located below wrap spring 135 and is in active communication with power sleeve 137. Connector sleeve 151 is configured to translate relative to, and independent from, mandrel 101 and power sleeve 137, along the axis of setting tool 100 when wrap spring 135 unwinds. An anti-rotation bolt 153 is configured to permit the translation of connector sleeve 151 along the axis of setting tool 100 but prevent relative rotation between connector sleeve 151 and mandrel 101 while setting tool 100 is in an unset position. Anti-rotation bolt 153 is threadedly coupled to mandrel 101. The head of anti-rotation bolt 153 protrudes into a portion of an aperture 155 that extends through connector sleeve 151. In the preferred embodiment, the shape of aperture 155 adjacent the exterior surface of connector sleeve 151 is circular; while the shape of aperture 155 adjacent the interior surface of connector sleeve 151 is U-shaped. The differences in shape within aperture 155 occur along edge 156, as seen in
Connector sleeve 151 is held in an unset position by a locking pin 147. Locking pin 147 is threadedly coupled to connector sleeve 151. A lower portion of locking pin 147 extends internally within a hook slot 149 formed within an exterior surface of power sleeve 137. Prior to activation of setting tool 100, wrap spring 135 is wound having a torsional preload configured to apply a torque or rotational force on power sleeve 137, so as to rotate power sleeve 137 relative to mandrel 101 in the direction indicated by arrow 50. This torque creates a binding force between the combinations of power sleeve 137 and locking pin 147 with that of anti-rotation bolt 153 and connecting sleeve 151. This binding force prevents the unwinding of power sleeve 137 as well as the translation of connector sleeve 151 until wrap spring 135 is released from upper portion 91. Power sleeve 137 is configured to selectively rotate around mandrel 101 and selectively permit the translation of connector sleeve 151 along the axis of setting tool 100.
External forces acting upon connector sleeve 151 and lower portion 93 may be relatively large. For example, such forces may approach 30,000 pounds. Hook slot 149 is oriented at an angle relative to the axis of setting tool 100 such that the external forces are divided into a combination of resultant forces. The orientation of hook slot 149, together with power threads 141 reduces the forces required to secure locking pin 147 within hook slot 149. For example, hook slot 149 may result in a 30 percent reduction of force required to maintain the binding force. Therefore the torsional preload on wrap spring 135 is reduced in order to retain locking pin 147 within hook slot 149. For example, the torsional preload may be reduced to 5 or 10 pounds.
When wrap spring 135 is released from short sleeve 127, wrap spring 135 unwinds thereby releasing the binding force on power sleeve 137 and locking pin 147. Power sleeve 137 is thereby permitted to rotate around mandrel 101. Axial external forces exerted upon connector sleeve 151 rotate power sleeve 137, such that locking pin 147 is removed from hook slot 149 and connector sleeve 151 is permitted to translate in a downward direction along the axis of setting tool 100.
Referring now particularly to
An outer piston 161 is integrally formed within an inner piston sleeve 163. Inner piston sleeve 163 is a cylindrical sleeve relatively concentric to the axis that is threadedly coupled to mandrel 101 at an upper end and is threadedly coupled to lower threaded portion 95B at a lower end. Because inner piston sleeve 163 is coupled to mandrel 101, inner piston sleeve is prevented from translating along the axis independent of mandrel 101. In this configuration, when wrap spring 135 is released from short sleeve 127, connector sleeve 151 translates along the axis in the direction of the arrows shown, but inner piston sleeve 163 does not translate. Although inner piston sleeve 163 has been described as being coupled to mandrel 101 without the ability to translate, other embodiments may permit translation of inner piston sleeve 163 by using slots and pins, for example.
Connector sleeve 151 extends around a periphery of inner piston sleeve 163. Connector sleeve 151 is configured to sealingly engage the exterior surface of inner piston sleeve 163 with one or more inner seals 164 coupled to connector sleeve 151. An outer piston sleeve 165 is threadedly coupled to a lower portion of connector sleeve 151 and extends around a periphery of connector sleeve 151 and inner piston sleeve 163, such that an outer chamber 167 is formed. Outer chamber 167 is a volume extending radially around setting tool 100 defined by the interior surface of outer piston sleeve 165 and the exterior surface of inner piston sleeve 163 as well as a lower face 168 of connector sleeve 151 and an upper face 169 of piston 161.
Outer chamber 167 is configured to retain a variety of fluids. In the preferred embodiment, the type of fluids held in outer chamber 167 are relatively incompressible fluids, such as oil. Fluids enter into outer chamber 167 through a fill hole 171 penetrating through outer piston sleeve 165. Although not shown, a bolt is releasably threaded into fill hole 171 to permit filling, draining, and to avoid the leaking of fluid. One or more outer seals 172 prevent the leakage of fluid between outer piston sleeve 165 and connector sleeve 151. One or more seals 174 prevent the leakage of fluid between outer piston sleeve 165 and piston 161. The use of seals 164, 172, and 174 extend around setting tool 100 and seal outer chamber 167.
Connector sleeve 151 and outer piston sleeve 165 are configured to translate as one body in the direction of the arrows shown in
Metering channel 175 is a volume extending around the periphery of a telescoping sleeve 177 and within the interior surface of inner piston sleeve 163. Telescoping sleeve 177 sealingly engages the inner surface of inner piston sleeve 163 above metering port 173 and extends lower relatively concentric to the axis adjacent lower threaded portion 95B. The lower end of metering channel 175 is sealed off by lower threaded portion 95B. Telescoping sleeve 177 is configured to permit the flow of fluid from outer chamber 167, through metering port 173, and between telescoping sleeve 177 and lower threaded portion 95B, such that fluid pressure acts upon an inner piston 179 and telescoping sleeve 177 to result in the translation of inner piston 179 and telescoping sleeve 177 in a direction opposite that of outer piston sleeve 165 and connector sleeve 151. The combination of telescoping sleeve 177 and inner piston 179 will be referred to as a telescoping piston.
Telescoping sleeve 177 and inner piston 179 are configured to translate along the axis independent of one another. Inner piston 179 slidingly engages the interior surface of telescoping sleeve 177. A seal 180 extends around inner piston 179 and prevents fluid from passing between telescoping sleeve 177 and inner piston 179. Telescoping sleeve 177 has an upper retaining clip 181 and a lower retaining clip 182. Retaining clips 181, 182 are configured to limit the translation of inner piston 179 independent from the translation of telescoping sleeve 177. Inner piston 179 has an upper flange 183 and a lower flange 184 extending around the circumference of inner piston 179. Flanges 183, 184 are configured to contact retaining clips 181, 182 respectively.
An inner chamber 185 is formed within setting tool 100. Inner chamber 185 is a volume defined as the space within the inner surface of inner piston sleeve 165, the lower end of mandrel 101 and the interior surfaces of the telescoping piston. Inner chamber 185 is filled with a compressible fluid, such as air for example. A spring 187 is located within inner chamber 185 and is biased against the lower end of mandrel 101 and upper flange 183. As the telescoping piston is translates, spring 187 and the fluid within inner chamber 185 is compressed within inner chamber 185. Telescoping piston is permitted to translate such that a face 188 of telescoping sleeve 177 contacts a mandrel face 189. Spring 187 is configured to exert a force upon the telescoping piston so as to return the telescoping piston adjacent to lower threaded portion 95B as the external forces are removed.
In order to illustrate how the various parts within setting tool 100 interact and move, a frame of reference is to be defined. Friction springs 105 press against casing 99, thereby exerting a certain amount of force, or resistance to motion. For illustrative purposes, friction springs 105 and the associated parts will be considered static while mandrel 101 and the associated parts will be considered dynamic.
Referring now also to
Referring now particularly to
An advantage of a multi-action index sleeve is the ability to avoid presetting of setting tool 100 while lowering within casing 99. Furthermore, multi-action index sleeves 111 provide a greater degree of safety in that they rely on repetitive mechanical inputs to operate.
Referring now particularly to
Referring now particularly to
Referring now particularly to
Referring now particularly to
Upon the subsequent lowering of mandrel 101, mandrel 101 is configured to translate an additional amount along the axis independent of index sleeve 111, swivel piece 125 and short sleeve 127. Upon the subsequent lowering of mandrel 101, index sleeve 111 and swivel piece 125 remain fixed in relation to L-slot pin 119. Retaining clip 129 contacts ledge 126, thereby preventing short sleeve 127 from separating from index sleeve 111. Therefore, mandrel 101 and sleeve bolt 130 continue along the axis. This extra translation permits wrap spring 135 to release from short sleeve 127 and in particular, spring slot 133. Wrap spring 135 now releases the torsional preload and permits power sleeve 137 to rotate freely.
Referring now particularly to
The present application provides significant advantages, including: (1) the ability to set a downhole completion tool without the use of explosives or electricity in the casing; (2) reduction in force required to secure lower portion 93; (3) ability to avoid premature setting of the downhole tool; (4) decreased costs associated with firing explosives; (5) decreased maintenance associated with explosives and electrical wiring; (6) increased success rate due to mechanical nature of the setting tool; and (7) mechanical nature of the setting tool allows for quicker resetting of the tool in preparation for the lowering of another downhole completion tool.
The method of operating setting tool 100 requires a number of steps. Upper portion 91 and lower portion 93 are arranged in an unset position. Wrap spring 135 is preloaded with a torque configured to rotate power sleeve 137 such that hook slot 149 applies a binding force on locking pin 147. A downhole completion tool is coupled to lower threaded portions 95A, 95B while a connecting line is coupled to upper threaded portion 97. Setting tool 100 is aligned with casing 99 and lowered by the connecting line to a desired depth. Once the depth is reached, tension is released from the connecting line resulting in mandrel 101 responding to external forces and translating further down casing 99. This motion causes index pin 115 to translate within index slot 113 thereby rotating index sleeve 111 around mandrel 101. A force is applied to mandrel 101 through connecting line moving mandrel 101 back up a distance within casing 99. This repeated force is the jolting forces discussed above. The jolting force incorporates the releasing and subsequent application of force on connecting line. Once sufficient jolting forces have been applied, setting tool 100 is activated and the downhole completion tool is set. Setting tool 100 may then be removed from casing 99 and prepared for additional work within casing 99.
While the preferred embodiment has been described with reference to an illustrative embodiment, this description is not intended to be construed in a limiting sense. Various modifications and other embodiments of the invention will be apparent to persons skilled in the art upon reference to the description.
The particular embodiments disclosed above are illustrative only, as the application may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. It is apparent that an application with significant advantages has been described and illustrated. Although the present application is shown in a limited number of forms, it is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof.
Greenlee, Donald R., Greenlee, Donald Jonathan
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